package com.atguigu.gmall.realtime.utils;

import java.util.concurrent.LinkedBlockingDeque;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

/**
 * Author: Felix
 * Date: 2022/4/28
 * Desc: 获取线程池工具类
 * 双重校验锁解决单例设计模式懒汉式线程安全的问题
 */
public class ThreadPoolUtil {

    private static volatile ThreadPoolExecutor poolExecutor;

    public static ThreadPoolExecutor getInstance(){
        if(poolExecutor == null){
            synchronized(ThreadPoolUtil.class){
                if(poolExecutor == null){
                    System.out.println("~~~创建线程池~~~");
                    poolExecutor
                        = new ThreadPoolExecutor(4,20,300, TimeUnit.SECONDS,new LinkedBlockingDeque<Runnable>(Integer.MAX_VALUE));
                }
            }
        }
        return poolExecutor;
    }
}
